Gun actuator



Feb. 15, 1944. .1. G. MEJEAN GUN AGTUATOR Filed June 16, 1941 3f w W vJ www Patented Feb. 15, 1944 UNITED STATES PATENT OFFICE GUN AorUA'ron Application June 16, 1941, Serial No. 398,351 In France February 1940 4 Claims.

This application relates to an expansible bellows device and particularly an eXpansible bellows device for use in a system for firing rapid-firing guns such as machine guns and light automatic cannon.

This application is a continuation-in-part of my co-pending application S. N. 378,285, filed February 10, 1941. In that application I describe a system for controlling the ring and recharging of machine guns and the like, particularly such guns are adapted to be mounted on aircraft. The

system there described is an electrical-pneumatic system in accordance with which a trigger or other element on the gun adapted to cause firing is moved by an expansible bellows device supplied by compressed air or other medium under pressure from a source carried on the aircraft, the admission of the medium under pressure to the bellows being controlled by an electrically actuated valve device.

The present invention is directed specically to a bellows-type actuator of the type shown in that application as disposed on the gun, and which has a portion adapted to be connected with the firing mechanism of the gun to actuate the same when the device is supplied with.k compressed air or some other medium under pressure.

One of the objects of the invention is to provide a device of the type referred to which is particularly adapted for use in aircraft, and which operates equally as well regardless of the altitude to whichit may be subjected when, for example, it is used for guns mounted on aircraft.

Another object of the invention is vthe provision of a bellows device for causing the initialflring Vof an automatic rapid-tiring gun, and which is extremely sensitive and accurate in operation. Because of its constructional form the invention, particularly when used with the system described in my co-pending application referred to above, is so sensitive as to permit the ring of one shot at a time even when the gun has a rate of're as high as 720 shots per minute.

Still a further object of the invention is the provision of a device of this type which is of simple construction, is made of lrelatively few parts, and is capable of being assembled and disassembled and replaced readily.

Other objects of the invention will become more claims when read in conjunction with the accom- ,panying drawing, in which:Y

ure 2;

.50 apparent from the following description and .tion I8 of the casing I2.

Figure 2 is a side cross-sectional view of one form of the invention; and

Figure 3 is a sectional view taken on the line 3-3 of Figure 2.

In the drawing the reference numeral IU indicates a supporting member for the actuating mechanism. The supporting member is adapted to be detachably secured to the gun (not shown). A casing l2 is threaded to the supporting member as at ML The casing is preferably cylindrical, as shown, and the lower portion thereof is of stepped construction to provide a concentric spring-receiving portion I6, and a smaller concentric actuating rod receiving portion I3, as clearly shown in Figure 2. The casing l2 and the supporting member ID together form a protective housing for the bellows arrangement which will now be described.

Within the housing and mounted in a circular recess in the supporting member It, is acircul'ar member 20 which is provided with an L-shaped passage 22 (see Figures 1 and 2). The circular member 2u is provided with a threaded opening 24 which connects with the passage 22. This threaded opening receives a tube 26. The tube 28 has a tube 28 mounted thereon and at right angles thereto. The end of tube 23 is in the form of an annulus so as to i'lt on the tube 2t and is held in place on thev tube 26 by being .pressed between a circular flange 3S on the tube The circular member 20 is provided with a central opening in which is disposed a bearing 36 adapted to receive the actuator rod 38 with a sliding t. 'Ihe other end of the rod 38 passes through an opening 40 in the rod receiving por- The rod 3U is'thus mounted for sliding movement in the direction Aof its longitudinal axis. The circular member 20 is also provided with a cut-out 42 for the purpose of making it lighter. y

Within the casing I2 is a member 4t which has a circular opening therein to permit it to surround the rod 38 to which it is rigidly secured by means of the screw 46. The member Mis provided with an outer annular ilange 48 which extends laterally from a portion 49 bent to form a deep annular space B. The inner wall of the bent portion 49 is spaced from the rod 38.

A generally cylindrical flexible corrugated metal tube 52 ris disposed within the casing I2 with its upper edge rigidly sealed to the member as by welding or the like. The lower edge of the corrugated tube 52 is likewise sealed to the flange 48 of the member 44. Another smaller tube 5d, similar to tube 52 and concentrically disposed with respect to tube 52, has its upper edge sealed to the lower surface of the member 20 and its lower edge sealed to an inwardly projecting flange 5S forming part of the member 44. The lower surface of this ilange, in turn, abuts a ange 5B on the rod 38 and thus aids in securing the member 44 to the rod.

A coil spring 60 is disposed with one end within the annular space 50 formed by the bent portion 49 in the member 45. The other end ofY the spring is disposed within the spring receiving portion I'S of the casing l2.

From the structure described it should be clear that the corrugated tubes 52 and 54, and

the member'M constitute an expansible bellows arrangement, which, when supplied with compressed air or the like through the L-shaped passage 22, will expand downwardly (Fig. 2) against the action of the spring 65, and in so expanding will draw down with it the rod 38.

When the'device is mounted'on a gun, the upper end oi the rod enters a portion of the gun where it is secured in such a manner (not shown) that downward movement of the rod i lires the gun. After the gun is red, the compressed air in the bellows is permitted to escape back through tube 28 by a valve device (not shown), and this permits the bellows to contract under action of the spring 6i) and thus returns rod 38 to its normal position. The lower end of the rod 3S may be provided with an opening 62 to permit a cord or cable to be attached thereto so that it may also be operated manually by pulling the cable downwardly. v

The device described possesses many advantages. It is, first of all, of simple construction and is made of relatively few parts and may be easily manufactured, assembled, and disassembled. Moreover, the particular bellows arrangement shown, with its welded Vair-tight construction, and with the bent portion 4S of the member 44 occupying a considerable amount of the space between the inner and outer walls of the bellows, renders the device capable of operation with only a small amount of compressed air or other medium. Still further, this last mentioned factor renders the actionof the bellows very quick and very accurate.

While obviously the device shown and described may be used in other systems and for other purposes, it is believed to have special advantages and to be admirably adapted to the type of system for firing 'guns described and claimed in my co-pending application Si. N. 378,285, of which as stated thisv present application is a continuation-impart.' y i 7 Moreover, it should be understood that changes in structure and arrangement may be made without departing from the essential concept of the invention, and that the invention should not be limitedl to the embodiment shown anddescribed except as may be indicated by the claims which follow.

I claim:

1. An expansible bellows type actuator adapted to be operated by a medium under pressure and comprising, a support, a cylindrical bellows wall, one end of which is sealed to said support, a closure member sealed to the other end of said bellows, a smaller cylindrica1 bellows wall disposed concentrically with respect to said iirst bellows wall, one end of said smaller bellows wall being sealed to said support and the other end being sealed to said closure member, said closer member being provided with a flange extending partially into the annular chamber formed by said concentric bellows walls passage means in said support for admitting a medium under pressure to the interior annular chamber between said larger and smaller cylindrical walls to expand the bellows formed by said Walls and said closure member, actuating means for urging said bellows to contracted position, said actuating means comprising a resilient member, said resilient member being adapted to engage said flange with one of its ends, the other of said ends being adapted to abut against said support, and an actuating member secured to said closure member to move therewith as the bellows expands and contracts, said actuating member passing through an opening in said support and through a central opening in' said closure member within and spaced from the circumference of said smaller cylindrical bellows wall.`

2. A bellows type actuator comprising, a support, said support having an opening therein, a rod slidably mounted in said opening and having an end adapted to actuate, when moved, the means to be actuated, a cylindrical corrugated bellows wall, one end' of which is sealed to said support, a smaller cylindrical corrugated bellows wall likewise sealed at onel end to said support, both of said bellows walls being disposedv concentrically surrounding said rod, a closure member sealed to the other ends of said bellows walls to close the annular space therebetween, said rod being secured to said closure member centrally of the latter, means for admitting compressed air to the annular space betweenthe cylindrical bellows walls to expandthe bellows formed byr said walls and closure member, spring means acting on said closure member in a direction urging said bellows to contracted position, a casing enclosing the bellows, said closure member having av portion bent to form an annular recess extending deeply within the annular space between the bellows walls, said spring means having one end disposed within said recess and the other end-supported by said casing.

3; A bellows type actuator comprising a substantially hollow casing, said casing being provided with a pair of oppositely disposed aligned openings, anactuating member slidably mounted in said openings, an annular supporting member within said casing, said annular member having a substantially inverted U-shaped cross section and being secured. toV said actuating member in coaxial alignment therewith, the arms of said' in- Verted U-shaped member being spaced from said actuatingmember, each free end of said arms being provided with a radially extending flange, a corrugated'metallic bellows disposed within said casing and in coaxial alignment with said actuating member, a second corrugated metallic bellows disposed concentrically withrespect' to said first'- said bellows, each of said bellows. having one of its endssealed to a wallof said casing, the other endv of each of sai'dbellowsv being sealed' to one of said flanges, spring means for urging said bel..

lows in one direction, said means having one of its ends abutting the leg of said inverted U shaped member, the opposite end of said spring means abutting a wall of said casing, and means for admitting a medium under pressure to the space between said bellows.

4. A bellows type actuator comprising a substantially hollow casing, said casing being provided withv a pair of oppositely disposed aligned openings, an actuating member slidably mounted in said openings, a supporting member secured to said actuating member in coaxial alignment therewith and extending radially therefrom, a corrugated metallic bellows disposed within said casing and in coaxial alignment with said actuating member, a second corrugated metallic bellows disposed concentrically with respect to said rstsaid bellows, each of said bellows having one of its ends sealed to a wall of said casing, the other end of each of said bellows being sealed to said supporting member, spring means for urging said bellows in one direction disposed intermediate said bellows, said spring means having one of its ends abutting a iiange formed o-n said supporting member, said ange being adapted for restricted movement between said bellows in a direction parallel to the longitudinal axis of said actuating member, the opposite end of said spring means abutting la wall oi said Casing, and means for admitting a medium under pressure to tbe space between said bellows.

JACQUES GUSTAVE MJEAN. 

